﻿// Copyright 2004-2011 Castle Project - http://www.castleproject.org/
// 
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// 
//     http://www.apache.org/licenses/LICENSE-2.0
// 
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#region 导入名称空间

using System;
using System.Collections;
using System.Collections.Generic;

#endregion

namespace LightWork.DynamicProxy.Generators
{
    public class TypeElementCollection<TElement> : ICollection<TElement>
        where TElement : MetaTypeElement, IEquatable<TElement>
    {
        private readonly ICollection<TElement> items = new List<TElement>();

        public int Count => items.Count;

        bool ICollection<TElement>.IsReadOnly => false;

        public void Add(TElement item)
        {
            if (item.CanBeImplementedExplicitly == false)
            {
                items.Add(item);
                return;
            }
            if (Contains(item))
            {
                item.SwitchToExplicitImplementation();
                if (Contains(item))
                    throw new ProxyGenerationException("Duplicate element: " + item);
            }
            items.Add(item);
        }

        public bool Contains(TElement item)
        {
            foreach (var element in items)
                if (element.Equals(item))
                    return true;

            return false;
        }

        public IEnumerator<TElement> GetEnumerator()
        {
            return items.GetEnumerator();
        }

        void ICollection<TElement>.Clear()
        {
            throw new NotSupportedException();
        }

        void ICollection<TElement>.CopyTo(TElement[] array, int arrayIndex)
        {
            throw new NotSupportedException();
        }

        bool ICollection<TElement>.Remove(TElement item)
        {
            throw new NotSupportedException();
        }

        IEnumerator IEnumerable.GetEnumerator()
        {
            return GetEnumerator();
        }
    }
}